Field of the Invention
The invention relates to a configuration for an optical device interface having a device and a main circuit board that is disposed remotely from the device and has a control device. The invention is used in franking machines when they are coupled optically to optional peripheral devices, or between stations in a mail processing machine.
Modern franking machines, because of their extensive electronics, are often susceptible to electrostatic charges and magnetic interference fields. For this reason, Published, European Patent Application EP 876 864 A2 has already proposed a configuration for communication between stations in a mail processing machine. In this case, although optocouplers are used, here they are only used for decoupling between the meter and base of the JETMAIL franking machine. The coupling between the stations in the mail processing machine is, however, again carried out electrically via plug-in connectors.
German Patent DE 196 05 015 C1, corresponding to U.S. Pat. No. 5,949,444, has already explained the printing device of the JETMAIL franking machine in more detail which, in a non-horizontal, approximately vertical transport of letters, carries out franking printing by an ink jet print head disposed in a stationary position in a recess behind a guide plate. A triggering sensor for the printing process is disposed shortly upstream of the ink jet print head recess. It is used to detect the start of a letter and interacts with an incremental transmitter for a travel control system. In the JETMAIL franking machine, the printing process is triggered by a transmitted light barrier in the franking machine (see Published, European Patent Application EP 901 108 A2). Using the latter, the leading edge of even particularly thick items of mail is unequivocally detected. In addition, in the JETMAIL franking machine, further optical sensors are used to detect the build-up of items of mail and for travel control. The aforementioned sensors and at least one sensor of an optional device are likewise connected to the control system of the franking machine. The device is, for example, a deposit box without its own voltage supply. In order to fulfil sensor functions of such an optional device, the transmission of a voltage requires a transmission of an electrical voltage between the devices, which are correspondingly configured for this purpose. Mounting all the sensors, including their fixing and equipment with plug-in connectors and with cables leading to the main circuit board in the devices, as well as the interfaces and cables for communication between the stations, necessitate high production costs, however. All the previous solutions, which use electrical interfaces with plug-in connectors and cables between the devices, on the one hand, and a sensor system with its own voltage supply in the optional devices, on the other hand, have to be protected in a complicated manner against electromagnetic interference fields.
It is accordingly an object of the invention to provide a configuration for an optical device interface which overcomes the above-mentioned disadvantages of the prior art devices of this general type.
The invention is based on the object of developing a configuration for an optical device interface which makes reliable, cost-effective data communication between a franking machine and optional devices possible, the latter being equipped with and without their own voltage sources. The optical device interface is intended to entail only low production costs. When fulfilling sensor functions in the optional device without its own supply voltage, the intention is to make the omission of the voltage supply devices possible.
With the foregoing and other objects in view there is provided, in accordance with the invention, a configuration for an optical device interface. The configuration contains a device having first optical waveguides and a franking machine disposed remotely from the device. The franking machine has a main circuit board, a transmitting and receiving unit disposed on the main circuit board, and second optical waveguides connected to the transmitting and receiving unit and communicating with the first optical waveguides. The transmitting and receiving unit communicates with the device by transmitting optical signals over the second optical waveguides.
In accordance with an added feature of the invention, the first optical waveguides detect objects at a measuring location disposed between the first optical waveguides in the device in accordance with a transmitted light principle known per se.
In accordance with an additional feature of the invention, the franking machine has a receiving diode disposed on the main circuit board and a print head, and the device has a circuit board and a transmitting diode disposed on the circuit board. The device has a transmitting location disposed in a stream of mail upstream of a printing location at which the print head of the franking machine can be positioned.
In accordance with another feature of the invention, the first optical waveguides are provided for data polling.
In accordance with a further feature of the invention, the transmitting and receiving unit has a transmitting diode disposed on the main circuit board, and the device has a circuit board and a receiving diode disposed on the circuit board.
In accordance with another added feature of the invention, the first optical waveguides and the second optical waveguides are for fixing and focusing a light beam and are transparent plastic optical waveguides.
In accordance with another additional feature of the invention, the transmitting and receiving unit has a clocked light-emitting diode to minimize stray light and increase a sampling reliability.
In accordance with another further feature of the invention, the franking machine has a print head, and the measuring location is disposed in the device along a mail stream upstream of a printing location at which the print head belonging to the franking machine can be positioned.
In accordance with a feature of the invention, the franking machine has a print head, and the measuring location is disposed in the device along a mail stream downstream of a printing location at which the print head belonging to the franking machine can be positioned.
In accordance with yet another feature of the invention, at the measuring location or the transmitting location in the device, various pieces of the first optical waveguides permit clocked polling of a plurality of sensors.
With the foregoing and other objects in view there is further provided, in accordance with the invention, a configuration for an optical device interface. The configuration contains a device, a main circuit board having a control device, a transmitting and receiving unit disposed on the main circuit board; and rigid pieces of optical waveguide connecting the device to the main circuit board. The transmitting and receiving unit communicate with the device by transmitting optical signals over the rigid pieces of optical waveguide.
A franking machine or another mail processing device which transports items of mail has a housing with an opening for the supply of items of mail. The franking machine has a main circuit board disposed in the interior for controlling the franking machine. The distance between the main circuit board of the franking machine to a location in an optional device is bridged by the inventive use of rigid pieces of optical waveguide. The rigid pieces of optical waveguide and the transmitting and receiving unit on the main circuit board are used for signal transmission in connection with the data communication and sensor systems in the optional devices.
Other features which are considered as characteristic for the invention are set forth in the appended claims.
Although the invention is illustrated and described herein as embodied in a configuration for an optical device interface, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.